This invention relates to a roll release mechanism for easy jam clearance, and more specifically, to an apparatus for solving problems of pinch rolls located just beyond the aligner gate in paper handling systems.
Pinch roll feed mechanisms are subject to the problem of jamming of the fed item. For example, paper sheets may jam in the pinch rolls of a copier or laundry articles may jam in the wringers of a washing machine. If a jam occurs, the design configuration of a particular apparatus may not allow the operator to reach the jammed item. If the item is reachable, the rolls may not be rotatable with the machine power off. If the rolls are not separable, the operator will most likely be required to tear out the item. This results in pieces of the jammed item remaining in the roll mechanism which can cause subsequent jam failures.
Roll release mechanisms are known which allow the machine operator to remove a jammed item. Most roll release mechanisms allow the rolls to be moved radially for jam clearance while maintaining the rolls in a parallel relationship. Such known mechanisms are operated manually and thus subject to operator error and slow operating speeds. Roll release mechanisms including automatic roll re-engagement upon machine start-up have reduced these problems. Such known mechanisms release by pivoting one roll at one end. Design of these mechanisms requires strict maintenance of tolerances in order to return the rolls to a precise parallel orientation upon roll re-engagement. Automatic roll re-engagement has always employed positive closure forces which mash fingers should they be caught in the apparatus. Finally, these roll release mechanisms occupy much space and consist of an extensive number of parts.